1. Field of the Invention
The present invention relates to the field of chamber blocks and specifically to removable chamber blocks for handguns or similar weapons.
2. Background Information
Gun safety is an increasingly important issue in the current political environment. Most of the discussion focuses on securing weapons in the home, especially where children are present. A different situation occurs in gun stores and at gun shows where weapons are offered for sale.
In an environment where weapons are offered for sale, there is a risk that a weapon may be loaded and fired, whether accidentally or intentionally. This risk leads to a desire to secure the weapons. However, the weapons must also be available for inspection and handling by the customers. This leads to a desire to leave the weapons unencumbered. Both problems are exacerbated in a gun show environment where high volumes of customers are handling the weapons and potentially buying.
The solution to this problem is most often described as a chamber block. This is a device which in some way blocks access to the chamber, preventing it from being loaded. Ideally, the chamber block will not interfere with any other operation of the weapon, but this goal is often not met.
Many designs for chamber blocks have been developed. Some utilize an element which fits within the chamber itself and grips the chamber walls in some manner to prevent removal of the block. One approach is to use two opposing parts which are drawn together, often by a threaded connection, causing one of the elements to offset or expand against the chamber wall or to compress a third element, such as an o-ring, which expands outward against the chamber wall. Another approach is to place one element within the chamber and connect it to another element positioned at the distal end of the barrel. The connecting element then draws them together, clamping them in position.
Most of the previous designs suffer from excess complexity with the resultant increased manufacturing and sale cost. Multiple parts are required and many require machined metal parts to handle the stresses inherent in their design.
Also inherent in the design of many existing chamber blocks is that all or part of the block must be inserted from the chamber end of the weapon. This can be inconvenient and may require partial disassembly, such as field stripping, of the weapon. This is inconvenient, especially where a wide variety of used weapons are displayed, each having a different stripping procedure.
When used weapons are being sold, it is especially important that the buyer have full access to inspect the weapon to determine wear, upkeep, and other characteristics unique to each weapon. Ideally, the buyer should be able to operate the weapon (such as working the slide), visually inspect the weapon, and even field strip the weapon as part of the inspection. Many chamber blocks and other safety devices interfere with this inspection process. This makes them undesirable and thus less likely to be used. Some existing solutions actually pose an increased safety risk by interfering with inspection. Those approaches which hold the slide closed do not allow verification that the chamber is not loaded, a check which is preferably performed by every person handling the weapon.
Ideally, a chamber block would also provide a visual indication that the weapon is safe. This would include a clear indication that the chamber itself is blocked, when viewed from the breach, and an external indication that the block is in place. Preferably the external indication would be visible from a significant distance, 15 or 20 feet as a minimum, so that other personnel can double check the use of the chamber block and easily verify that all displayed weapons are properly blocked. Few if any existing chamber blocks address this requirement.
It is important to note that the above problem is not that typically addressed by gun locks and chamber blocks do not serve as gun locks. A chamber block is intended for use where the weapon is under supervision by a responsible party but is being handled by a customer or other person. There is a need to hinder or restrict the ability to load the weapon, but minimal interference with inspection must also be achieved. Because supervision is always present, a lower level of security than that provided by a gun lock is suitable.
There is a need for a chamber block which is easy to use, inexpensive to manufacture, and which offers minimal interference with inspection of the weapon on which it is installed. Ideally, the device would block access only to the chamber itself and the inside of the barrel. Preferably, the block will be insertable from the barrel end of the weapon. The block should be sufficiently inexpensive that a dealer can reasonably afford to install a chamber block on every weapon on display. Ideally, it will provide a visual indication that it is in place and that the chamber is blocked. This indication should be apparent both from a distance and when inspecting the chamber of the weapon. Of course, the chamber block must also operate without damaging the weapon or its finish in any manner.